The party's latest poster is adorned with the same pair of red eyes used in a widely criticised campaign against Labour, plus a pair of orange eyes which are equally menacing.
Its slogan, "Lib Dem-Labour - Double Danger" suggests that the Tories fear an alliance of the two opposition parties after the election.
The Liberal Democrats' chair of campaigns, Nick Harvey, wrote to Brian Mawhinney last night complaining that he had made false claims about the party's policies.
A leaflet bearing the new image and handed out in the West Country said a vote for the Liberal Democrats was a vote for the legalisation of drugs such as cannabis, for a United States of Europe, for Brussels control of immigration and defence, for higher taxes and for weak, multi-party government.
The party has agreed to set up a Royal Commission which would consider decriminalising cannabis, but would not legalise it. However, its conference has voted in favour of the move in the past.
Last night, Mr Harvey said his party would retain European veto on immigration and defence, would cut some taxes and would offer a strong government based on consensus.
"Lies and smears demean the political debate and are not enough to save Tory skins. Brian Mawhinney must correct the lies, withdraw the mistaken attacks and recall the disgraceful posters and literature immediately," he said.
A Conservative Party spokesman said the points made all related to aspects of Liberal Democrat policy.
"The Liberals are running scared on this because they have been found out. These points will be driven home to the electors in the West Country in the weeks ahead," he said.Reuse content